Lock for nuts and screw heads



p 927 A. KLAFKE LOCK FOR NUTS AND SCREW HEADS Filed Nov. 18, 1926 3 Sheets-Sheet),

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1,643, 4 Sept. 27, 1927. A KLAFKE 38 LOCK FOR NUTS AND SCREW HEADS Filed Nov. 18, 1926 3 Sheets-Sheet 2 Sept. 27, 1927. ,384

A. KLAFKE LOCK FOR NUTS AND SCREW HEADS Filed Nov. 18, 1926 s Shets-Sheet :5

Patented Sept. 27, 1927.

UNITED. STATES 1 ALBERT KLAFKE, 0F MUNICH, GERMANY.

LOOK FOR NUTS AND SCREW HEADS.

Application filed November 18, 1925, Serial No. 149,117, and in Germany October 14,. 1923.

This invention relates to a lock for nuts and screw heads. The invention consists essentially in utilizing for locking the nut or the screw head a washer having an upwardly turned inner edge or upwardly turned extensions on the inner edge designed to engage with an outwardly inclined groove of the nut to lock the same. The upwardly turned ed e or the upwardly turned projections 0 the washer are tightly upset in the groove or cavity of the nut when the nut is being screwed tight, whereby a secure connection between nut and washer iscreated.

The washer is secured against rotation, by any convenient means, the nut rigldly connected to the washer being at the same time locked against accidental rotation.

Several embodiments of the inventlon are shown, by way of example, on the accoms panying drawing in wh1ch I Fig. 1 shows in longitudinal section a nut according to the invention,

Fig. 2 shows in section and Fig. 3 in top plan view the corresponding washer. a

Fig. 4 shows in longitudlnal section the nut and the washer in the locked position on a screw bolt which is shown in elevation.

Fig. 5 shows in longitudinal section a washer of modified construction.

Fig. 6 shows in longitudinal section a nut of modified construction.

Fig. 7 shows in side elevation and Fig. 8 in top plan view a third form of construction of the washer.

Figs. 9 and 10 show in longitudinal section the upwardly turned projections of the washer shown in Figs. 7 and 8.

Fig. 11 shows in longitudinal section and Fig. 12 in top plan view a further form of construction of the nut.

Fig. 13 shows in top plan view the improved nut lock used on railway sleepers in combination with a helical spring.

Fig. 14 is a cross section'of Fig. 13.

Fig. 15 shows in section, partly in elevation, the washer with spring prior to the tightening of the nut.

Fig. 16 shows in a section on line 16 16 of Fig. 13 the washer after the tightenlng of the nut.

Fig. 17 shows in side elevation and Fig. 18 in top plan view a modified construction of the Washer shown in Figs. 13 to 16.

Referring'to the drawings a is the nut and b the washer. The washer has an upwardly turned inner edge '0 fitting into a cavity d of the nut a. The cavity 03 is produced for instance by backing ofl of the nut which nut may have at this part a thinner wall. The cavity d might however be produced by slitting the wall of the nut.

collar of the washer b is slit or subdivided into stud-like portions which are higher than the cavity (1 in the nut is deep. The conical portion 7 of the circular thread of nut a comes into contact with the inner edge of the collar 0 of the washer when the nut is being screwed on. When the nut is being t ghtened the collar 0 or the stud like portions of the same are'pressed in outward direction so that the collar slips behind the conical portion g of the nut 11 formed by the cavity 03. As the collar 0 is higher than the cavity (1 of nut a is deep, the collar 0 or the stud like parts of the same are upset when the nut is tightened so that its lower surface rests upon the top surface of the washer b, so that the collar or the stud like the same are strongly compressed tween the walls of the conical portion of the cavity d and securely connected with the nut (Fig. 4). The secure connection between, washer and nutmay be further increased by roughening or fiuting the stud like parts of collar 0 or the cavity (1? of the nut on the inner and outer walls or on the inner or on the outer wall. .By the pressure exerted by the upset parts of collar 0 the threads of nut a are tightly pressed into the threads of the screw bolt h (Fig. 4).

The subdivided collar 0 of the washer b may be bevelled on the outer side. Fig. 5 shows, for instance a washer the stud like parts of the collar 0 of which are alternately bevelled on the top edge of the outer and inner surface. The studs or parts of the collar c which are bevelled on the inner side may be longer than those bevelled on the outer side. When washers are shown in Fig.

5 are used the studs or parts of the collar 0 which are bevelled on the inner side are pressed into the cavity 03 of the nut when said nut is tightened, whilst the studs or parts of the collar 0 which are bevelled on the outer side are ressed inward into the threads of screw (Fig. 4). In connection with a washer as shown in Fig. 5 a nut as The upwardly turned inner edge 0, or

arts of,

shown in Fig. 6 is preferably used which com rises, besides the conical surfaces f, g of t e cavit d, a conical Surface s WhlCh 1s inwardl directed towards the thread and with Whlch the studs or parts of collar 0 come into engagement which are bevelled on the outer'side so that they are pressed inwardly into the thread of the screw bolt it.

As shown in Fig. 7 to 10 the studs or parts of the collar 0 may be of difierent thickness. The studs 0 designed to be pressed mwardly into the thread of the screw bolt are thinner than the studs 0 designed to be pressed out- 'conical walls of cavity d. Owing to the cut out portions e at least one stud 0, instead of being upset, will be pressed outwards inf to engagement with the'cut out portion e.

When the cut out portions e are unsymmetrically arranged with regard to the symmetrical arrangement of the studs 0 of the washer b one of the studs 0 will engage with one of "the cut out portions 0 of the nut after a slight rotation of the nut a so that this nut is automatically locked by this stud of the washer. In this form of construction all the studs 0 may be bevelled on the inner side.

When the cut out portions 6 of the nut are displaced with regard to the symmetrical arran ement of the studs or parts of collar 0 of t e washer b they might form together with the gap between two studs 4 continuousopenings into which, for instance, a. cotter, split pin or the like might be inserted.

The washer b may be of various constructions in order to prevent turning of the washer. With this object in view the washer 6 might be flat on one side (Fig. 3) or it might be roughened, fluted or have pyramidshaped, cone shaped or Apointed projections i (Fig. 5) on one side. t certain points of the washer flaps might be stamped out of the washer so'that they project towards the support for the washer (Figs. 7 and 8) The resilient flaps t exert a locking action against accidental backward rotation of the nut or of the washer.

The inventionmight be used in connection with the spring washers for the screw connection of railway rails or sleepers, as shown in Figs. 14 to 16. In these figures of the drawing 25 is the washer which has the inner edge 0 turned up, said edge being eventually subdivided into several stud-like arts. The washer b has at the outer edge ownwardly bent flaps 1' and it is designed to accommodate a helical spfin a (Fig. 15-). The outer edge of the was er has cut out'portions 1) so that the flat ortion of the washer, the inner edge of whic forms the vertical collar 0, can bend downwards at the ti htening of the nut and ut the spring u un er tension (Fig. 16). W1th this object in view the fiat portion of the washer which carries the upwardly turned collar 0 is elastic, z is the art of the rail and sleeper connection in w ich T5 the washer, nut and spring u are located.

The washer b may be reinforced by ribs y (Figs. 17 and 18) extending from the flat portion over the bent outer edge and the downwardly directed flap 1'. These flaps 1' may grip over projecting portions of the rail and sleeper connection and they might be provided on one side only.

The described lock device can also be used in combination with the head of screw'bolts, in which case the head of the bolt instead of the screw-nut is provided with the described cavit d.

I c aim 1. A look for nuts and screw heads, comprising'in combination, a nut having a cav- 1ty in the lower surface, and a Washer, an upwardly turned collar on the inner edge of said washer subdivided into several se arated stud like parts designed to indepen ently engage with and be bent by said cavity of said nut to lock said nut in its position.

2. A look for nuts and screw heads comprising in combination, a, nut havin a cavity in the lower surface, and a was er, an upwardly turned collar on the inner edge of said washer subdivided into several separated stud like parts bevelled on one side of the top edges and designed to independent- 1y engage with and be bent by said cavity of said nut to lock said nut in its position.

3. A lock for nuts and screw heads, comprising in combination, a nut having a cavity in the lower surface, and a washer, an upwardly turned collar on the inner edge 0 said washer subdivided into several stud like parts alternately bevelled on the one side and on the other side of said edges and designed to engage with said cavity of said nut so that said stud like arts are bent inward or outward by the tig tened nut tolock said nut in its position.-

4. A look for nuts and screw heads, comprising in combination, a nut having a cavity in the lower surface, and a washer, an upwardly turned collar on the inner ed e of said washer subdivided into several stu like parts of different thickness and designed to engage with said cavity of said nut to lock said nut in its position.

5. A lock for nuts and screw heads, comprising in combination, a nut having a cav- -ity in the lower surface, and a washer, an

upwardly turned collar on the inner like parts of different length and designed to engage with said cavity of said nut to lock said nut in its position.

6. A look for nuts and screw heads, comprising in combination, a nut having a cavit Y in the lower surface formed by a backed 0 slot and having cut out portions, and a washer, an u Wardly turned collar on the inner edge 0 said washer subdivided into several stud like parts and designed to engage with said cavity of said nut, some of said stud like parts designed to engage with some of said out out portions of said nut, to lock said nut in its position.

7. A look for nuts and screw heads, comprising inv combination, a nut having a cavity in the lower surface, and a washer, an upwardl turned collar on the inner edge of said was er subdivided into several stud like parts alternately bevelled on the one side and on the other side of said edges and designed to engage with said cavity of said nut, and a cone in said nut turned towards the thread, so that some of said stud like parts are bent inward by the tightened nut to engage with the threads of thescrew bolt,

to lock said nut in its position.

said cavity of said nut and to be upset when said nut is being turned to lock said nut in its position, and a helical spring underneath said washer.

9. A lock for nuts and screw heads, comprising in combination, a nut having a cavity in the lower surface, and a washer, an upwardly turned collar on, the inner edge of said washer, and designed to engage with said cavity of said nut and to be upset when said nut is being turned to lock said nut in its position, a downwardly turned flange at the outer edge of said washer, and a helical. spring underneath and inside the downwardly turned flange of said washer.

10. A lock for nuts and screw heads, comprising in combination, a nut having a cavity in the lower surface, and a washer, an upwardly turned collar on the inner edge 0 said washer and designed to engage with said cavity of said nut and to be upset when said nut is being turned to lock said nut in its position, a downwardly turned flange at the outer edge of said. washer, the flat portion of said washer having stamped out downwardly directed flaps so that it is elastic, and a helical spring underneath and inside the downwardly turned flange of said washer.

In testimony whereof I aflix my signature.

ALBERT KLAFKE. 

